The professional conduct of attorneys is generally regulated by each state's rules of professional conduct—which are often written by the state's highest court, and enforced through the disciplinary process administered by the state's bar association. The professional conduct of attorneys is also referred to as legal ethics and professional responsibility.

Attorneys can be disciplined for a variety of reasons, ranging from the failure to pay their bar dues to misappropriating client funds. The grounds upon which an attorney may be disciplined by the state bar association are generally located in the state bar association's disciplinary rules of professional conduct.

Some attorneys who have been disciplined are no longer eligible to practice law. You should inquire about an attorney’s disciplinary history on the state bar association’s website, or by calling the state bar association.

You should not hire an attorney whose license is been suspended or revoked and who is not eligible to practice law in your state. Each state has a disciplinary organization that receives, investigates, and resolves ethics complaints against attorneys licensed in the state.

In Illinois, the professional conduct of attorneys is regulated by the Illinois Rules of Professional Conduct, which are established by the Illinois Supreme Court. The Attorney Registration and Disciplinary Commission (ARDC) is the organization responsible for administering the attorney disciplinary system in Illinois. Attorneys in Illinois can face discipline for various reasons, including but not limited to non-payment of bar dues, misappropriation of client funds, conflicts of interest, and other breaches of ethical duties. The ARDC investigates complaints against attorneys, and disciplinary actions can range from censure or reprimand to suspension or disbarment. It is crucial for clients to check an attorney's disciplinary history before hiring them, which can be done through the ARDC's website or by contacting the ARDC directly. Hiring an attorney whose license has been suspended or revoked is not advisable, as they are not permitted to practice law in Illinois.